A substantial expenditure of time and resources is associated with restocking and resupplying operations, for example, the loading of articles into a vending machine. In a typical restocking procedure, a package containing an article is brought close to the machine to be resupplied, the package is opened, and the article is loaded into the machine. In many situations it is necessary to keep track of the origin of the articles being loaded, at what time the resupplying occurs, etc. This can be motivated by accounting and billing considerations; or to prevent fraud, unauthorized stock transfer, and the like; or it may be required to allow the operation of the article and/or the vending machine itself. The manual recording of the resupplying event has associated costs, and entails the possibility of errors and delays.
Game ticket vending machines are a good example of the need for tracking such articles in real time. Instant lottery tickets, such as “scratch-off” or “pull-tab” tickets, if valid or activated, may be equivalent to cash. Accordingly, their handling requires extensive safeguarding and careful control, similarly to the handling of currency. To prevent errors and abuse, some types of game tickets must be activated at the time they are loaded into a game ticket vending machine. These tickets are often wholesaled to retailers on a consignment basis; The retailers may be charged for tickets only when they are activated. At the time of loading a set (or “book”) of tickets into a vending machine, an operator or retailer may need to transmit the ticket information to a central service or host computer in order to validate the tickets for play. Depending on the particular application and on the level of technical sophistication, the level of detail of the transmitted information may range from a single identifier for an entire “book” of game tickets to detailed information on individual game tickets.
Radio frequency identification (RFID) technology offers an economical way for tracking small items during transportation and storage. An RFID tag is essentially a transmitter that can be embedded in the packaging of an article or in the article itself, and transmit information about the location of the article, its date of manufacture, its origin and destination, etc. The signal transmitted from the RFID tag is received by a reader, usually a larger, fixed radio receiver that in turn may be part of a larger wired or wireless data network. An RFID tag can also receive information from the reader or from other sources (built-in sensors, wired and wireless networks, etc) and store this information in a built-in memory, for example recording events such as shipping, usage, and even tampering.
An RFID tag can be passive, receiving power from the reader through electromagnetic radiation, or active, having its own source of power, for example a battery. Semi-passive RFID tags comprise a source of power for the internal circuitry, but draw power from the reader for radio transmission. In the following, by ‘passive RFID tag’ we will also denote semi-passive tags.
Possible applications proposed for RFID technology include tracking of containers and rail cars, retail-level packaging, personnel identification and access control. A host of RFID products and applications are being introduced by major semiconductor, computer and software companies. Standards for RFID equipment and communication protocols have been published by ISO (International Standards Organization), IEC (International Electro-Technical Commission) and AIM (Association for Automatic Identification and Mobility).
RFID tags may be used to track articles as they move along the supply chain, by placing readers at key locations, for example in handling and storage facilities. However, accidental transmission may occur during transportation and storage if the RFID tag is for any reason brought too close to a reader which is located at a different stage along the supply chain. For example, an article could be stored in the same location where the article is intended to be used, so that a reader designed to detect the usage of the article could incorrectly detect RFID tags attached to articles being stored, and vice versa. The exact range of communication for RFID technology depends on the power of the RFID tag transmitter and the sensitivity of the reader, as well as on environmental conditions such as bodies causing signal reflections and sources of interference. Therefore, it may be impractical to rely on the RFID tag being in or out of the range of a specific reader.
U.S. Pat. No. 6,628,764 to Petite and U.S. Pat. No. 6,658,248 to Lee describe vending machines using radio communication to interact with the users and/or with the service provider.
U.S. Pat. No. 6,121,544 to Petsinger describes a holder with shielding properties, that may prevent surreptitious access to contactless smartcards.
U.S. Pat. No. 5,617,812 to Balderson et al. and U.S. Pat. No. 4,793,489 to Israel describe the use of diffusion of various types of gas to detect the opening of a container of perishable goods such as food.
Two pending U.S. patent application (application Ser. No. 10/392,618, filed on Mar. 19, 2003, to Meehan; application Ser. No. 10/723,410, filed on Nov. 24, 2003, to Meehan et al.) describe the use of RFID technology in game tickets. These applications are assigned to the owner of the present application.